214 
leaf), on quite long (0.310 mm.) pedicels ; whole length of sporo- 
phydium (except its pedicel), 0.835 (-900); length of coronula, 
0.120. Coronula of roundish cells not elongated. Nucleus, 
when mature, smooth, black, with 9-10 faint stria, and with two 
sharp points at the base, 0.620-.645 long, 0.310-.330 broad. 
When immature, the angles are strong and winged. 
On one verticil two small abortive antheridia were seen on 
the outside, occupying the place of stipules, opposite the leaves. 
No sporophydia occur in this position, but sometimes the long- 
stalked sporophydia turn down between the leaves and appear 
to be situated externally. 
Antheridia on the first node of the leaf, separated from the 
sporophydia, 400 #. in diameter; rarely situated on the outside 
of the verticil. 
This form differs in some respects from the description of ‘the 
one from the rice-fields in an oasis of the Libyan desert. That 
species grew in salty water, had spreading leaves, and the aspect . 
of a “large Ch. aspera or a moderate Ch. contraria,” but the size 
of the fruit and the other peculiarities lead me to unite this form 
with that species. 
Fig. 1— A mature verticil, with minute opposite stipules and 
pedicellate sporophydia within the verticil of leaves. Fig. 2—A 
mature nucleus. Fig. 3—-Small abortive antheridia outside the 
verticil. Fig. 4—A young verticil, with immature sporophydia, 
with a mature antheridium on the first node of the leaf. 
All figures magnified 40 diameters. 
A NEW NITELLA FROM NANTUCKET.—(PLATE LXXV.) 
NITELLA MoRONGH, n. sp. Diarthrodactyla, homceophylla, 
monoica, macrodactyla, sub-flabellata. 
Plant 5-6 inches high; lower leaves sterile, elongated, once 
or twice divided, mucronate; upper leaves contracted, forming 
with their stems fertile spikes; fertile verticils numerous, crowded 
in terminal and axillary spikes about half an inch long; leaves 
of fertile verticils short, twice divided in the lower, once divided 
in the upper verticils. Leaves in a verticil, six ; first division 
about 240 p. long, 95 in diameter; terminals, usually four, of 
when bearing fruit three, 460 long, 80 in diam., not accuminate 5 
